Validation of Placebo in a Manual Therapy Randomized Controlled Trial

Reduction of Chronic Primary Low Back Pain by Spinal Manipulative Therapy is Accompanied by Decreases in Segmental Mechanical Hyperalgesia and Pain Catastrophizing: A Randomized Placebo-controlled Dual-blind Mixed Experimental Trial

Chronic primary low back pain (CPLBP) refers to low back pain that persists over 3 months, that cannot be explained by another chronic condition, and that is associated with emotional distress and disability. Previous studies have shown that spinal manipulative therapy (SMT) is effective in relieving CPLBP, but the underlying mechanisms remain elusive. This randomized placebo-controlled dual-blind mixed experimental trial (NCT05162924) aimed to investigate the efficacy of SMT to improve CPLBP and its underlying mechanisms. Ninety-eight individuals with CPLBP and 49 controls were recruited. Individuals with CPLBP received SMT (n = 49) or a control intervention (n = 49), 12 times over 4 weeks. The primary outcomes were CPLBP intensity (0-100 on a numerical rating scale) and disability (Oswestry Disability Index). Secondary outcomes included pressure pain thresholds in 4 body regions, pain catastrophizing, Central Sensitization Inventory, depressive symptoms, and anxiety scores. Individuals with CPLBP showed widespread mechanical hyperalgesia (P < .001) and higher scores for all questionnaires (P < .001). SMT reduced pain intensity compared with the control intervention (mean difference: -11.7 [95% confidence interval, -11.0 to -12.5], P = .01), but not disability (P = .5). Similar mild to moderate adverse events were reported in both groups. Mechanical hyperalgesia at the manipulated segment was reduced after SMT compared with the control intervention (P < .05). Pain catastrophizing was reduced after SMT compared with the control intervention (P < .05), but this effect was not significant after accounting for changes in clinical pain. Although the reduction of segmental mechanical hyperalgesia likely contributes to the clinical benefits of SMT, the role of pain catastrophizing remains to be clarified. PERSPECTIVE: This randomized controlled trial found that 12 sessions of SMT yield greater relief of CPLBP than a control intervention. These clinical effects were independent of expectations, and accompanied by an attenuation of hyperalgesia in the targeted segment and a modulation of pain catastrophizing.

Seeing the Truth About Double Blinding

Randomized clinical trials provide reassurances that confounding factors are balanced at baseline whereas blinding is essential to assure the balance of extraneous factors thereafter. This article provides a three-part taxonomy of pitfalls that can arise because of inadequate blinding in clinical trials. We introduce a cautionary framework for readers interpreting a blinded randomized trial for evidence-based medicine. Each pitfall is illustrated with a relevant example of a potential bias resulting from knowledge of group assignment. Several pitfalls occur during the conduct of the study including inadequate blinding of the intervention group, control group, or responsible clinicians. Additional pitfalls relate to data analysis including unsubstantiated assertions of blinding and subverted tests for blinding. Further pitfalls arise due to surrounding oversight including unblinding of research ethics boards and scientific reviewers. These caveats are sources of misunderstanding when observing the apparent connection between a clinical intervention and patient outcomes. An awareness of specific pitfalls might help advance the interpretation and application of blinded randomized clinical trials to inform evidence-based medical care.

One spinal manipulation session reduces local pain sensitivity but does not affect postural stability in individuals with chronic low back pain: a randomised, placebo-controlled trial

BACKGROUND

Clinical practice guidelines recommend spinal manipulation for patients with low back pain. However, the effects of spinal manipulation have contradictory findings compared to placebo intervention. Therefore, this study investigated the immediate effects of lumbar spinal manipulation on pressure pain threshold (PPT) and postural stability in people with chronic low back pain (cLBP). Second, we investigated the immediate effect of lumbar spinal manipulation on pain intensity and the interference of the participant beliefs about which treatment was received in the PPT, postural stability, and pain intensity.

METHODS

A two-arm, randomised, placebo-controlled, double-blind trial was performed. Eighty participants with nonspecific cLPB and a minimum score of 3 on the Numeric Pain Rating Scale received one session of lumbar spinal manipulation (n = 40) or simulated lumbar spinal manipulation (n = 40). Primary outcomes were local and remote PPTs and postural stability. Secondary outcomes were pain intensity and participant's perceived treatment allocation. Between-group mean differences and their 95% confidence intervals (CIs) estimated the treatment effect. One-way analysis of covariance (ANCOVA) was performed to assess whether beliefs about which treatment was received influenced the outcomes.

RESULTS

Participants had a mean (SD) age of 34.9 (10.5) years, and 50 (62.5%) were women. Right L5 [between-group mean difference = 0.55 (95%CI 0.19 to 0.90)], left L5 [between-group mean difference = 0.45 (95%CI 0.13 to 0.76)], right L1 [between-group mean difference = 0.41 (95%CI 0.05 to 0.78)], left L1 [between-group mean difference = 0.57 (95%CI 0.15 to 0.99)], left DT [between-group mean difference = 0.35 (95%CI 0.04 to 0.65)], and right LE [between-group mean difference = 0.34 (95%CI 0.08 to 0.60)] showed superior treatment effect in the spinal manipulation group than sham. Neither intervention altered postural stability. Self-reported pain intensity showed clinically significant decreases in both groups after the intervention. A higher proportion of participants in the spinal manipulation group achieved more than two points of pain relief (spinal manipulation = 90%; sham = 60%). The participants' perceived treatment allocation did not affect the outcomes.

CONCLUSION

One spinal manipulation session reduces lumbar pain sensitivity but does not affect postural stability compared to a sham session in individuals with cLPB. Self-reported pain intensity lowered in both groups and a higher proportion of participants in the spinal manipulation group reached clinically significant pain relief. The participant's belief in receiving the manipulation did not appear to have influenced the outcomes since the adjusted model revealed similar findings.

The effects of chiropractic adjustment on inattention, hyperactivity, and impulsivity in children with attention deficit hyperactivity disorder: a pilot RCT

Background

Attention deficit hyperactivity disorder (ADHD) is a neurobiological disorder characterized by inattention, hyperactivity, and impulsivity. We hypothesized that chiropractic adjustments could improve these symptoms by enhancing prefrontal cortex function. This pilot study aimed to explore the feasibility and efficacy of 4 weeks of chiropractic adjustment on inattention, hyperactivity, and impulsivity in children with ADHD.

Methods

67 children with ADHD were randomly allocated to receive either chiropractic adjustments plus usual care (Chiro+UC) or sham chiropractic plus usual care (Sham+UC). The Vanderbilt ADHD Diagnostic Teacher Rating Scale (VADTRS), Swanson, Nolan and Pelham Teacher and Parents Rating Scale (SNAP-IV), and ADHD Rating Scale-IV were used to assess outcomes at baseline, 4 weeks, and 8 weeks. Feasibility measures such as recruitment, retention, blinding, safety, and adherence were recorded. Linear mixed regression models were used for data analysis.

Results

56 participants (mean age ± SD: 10.70 ± 3.93 years) were included in the analysis. Both the Chiro+UC and Sham+UC groups showed significant improvements in total and subscale ADHD scores at 4 weeks and 8 weeks. However, there were no significant differences between the two groups.

Conclusion

This pilot study demonstrated that it was feasible to examine the effects of chiropractic adjustment when added to usual care on ADHD outcomes in children. While both groups showed improvements, the lack of significant between-group differences requires caution in interpretation due to the small sample size. Further research with larger samples and longer follow-up periods is needed to conclusively evaluate the effects of chiropractic adjustments on ADHD in children.

Feasibility of blinding spinal manual therapy interventions among participants and outcome assessors: protocol for a blinding feasibility trial

INTRODUCTION

Blinding is a methodologically important aspect in randomised controlled trials yet frequently overlooked in trials of spinal manual therapy interventions for back pain. To help inform the blinding methods of a future, double-placebo-controlled trial comparing spinal manual therapy and nerve root injection for lumbosacral radicular pain, we set four objectives: (1) to assess the feasibility of blinding participants, randomly allocated to an active or placebo-control spinal manual therapy intervention protocol, (2) to assess the feasibility of blinding outcome assessors within the trial, (3) to explore the influence of spinal manual therapy experience and low back pain on blinding, and (4) to explore factors contributing to perceptions about intervention assignment among participants and outcome assessors.

METHODS AND ANALYSIS

Two-parallel-group, single-centre, placebo-controlled, methodological blinding feasibility randomised trial. We will recruit between 60 and 100 adults with or without back pain and with or without experience of spinal manual therapy from Zurich, Switzerland. Participants will be randomised to either an active spinal manual therapy or a placebo-control spinal manual therapy protocol-both interventions delivered over two study visits, up to two weeks apart. The primary outcome is participant blinding using the Bang blinding index within each intervention arm immediately after each of the two study visits. Secondary outcomes are participant blinding using the James blinding index, outcome assessor blinding (Bang and James blinding indices), self-reported factors influencing perceived intervention assignment among participants and outcome assessors, and participant-reported credibility and expectancy of study interventions. Other outcomes-included to blind the study objective from participants-are lumbar spine range of motion, self-rated general health, satisfaction with care, pain intensity, and function. Intervention provider outcomes include intervention component fidelity and quality of intervention delivery.

ETHICS AND DISSEMINATION

The independent ethics commission of Canton Zurich granted ethical approval for this study (KEK 2023-00381). Written informed consent will be obtained from all participants. Findings will be disseminated in scientific conferences and a peer-reviewed publication and inform the blinding methods of a future double-placebo controlled trial comparing spinal manual therapy and nerve root injection for lumbosacral radicular pain-the SALuBRITY trial.

TRIAL REGISTRATION

NCT05778396.

Efficacy and safety of the orthopaedic manipulation techniques of the Lin School of Lingnan Region in the treatment of adolescent idiopathic scoliosis: protocol of a participant-and-assessor-blinded randomized controlled study

BACKGROUND

Adolescent idiopathic scoliosis (AIS) is the most common developmental spine disorder among children. It is characterized by a lateral deviation of the spine that gives rise to the distinctive "S" or "C" shaped bending of the spine. The Lin School of Lingnan Region (LSLR), one of the prominent schools for bare-handed orthopaedic manipulation in southern China, provides preliminary evidences that the orthopaedic manipulation techniques help to correct deviations of the spine. Previous research found that Orthopaedic Manipulation Techniques of LSLR (OMT-LSLR) could reduce the Cobb's angles in patients with AIS. Therefore, the current study aims to investigate the effectiveness and safety of the OMT-LSLR in treating teenagers with AIS.

METHODS

In this participant-and-assessor-blinded randomized controlled clinical trial, 50 participants identified AIS without surgical indications will be recruited and randomized into two groups to receive physiotherapy scoliosis-specific exercises training with either orthopaedic manipulation or sham manipulation treatment for 16 weeks, followed by post-treatment visits at week 24. Primary outcome measure is the change of Scoliosis Research Society-22 (SRS-22) questionnaire score. Secondary outcome measures include Traditional Chinese version of Spinal Appearance Questionnaire (TC-SAQ) score, Italian Spine Youth Quality of Life (ISYQOL) score, the change of Cobb's angle measured by Xray, and the change of Cobb's angle, spinal rotation and muscle volume measured by three-dimensional (3D) ultrasound. The trial will be conducted at the Chinese University of Hong Kong Chinese Medicine Specialty Clinic cum Clinical Teaching and Research Centre in Hong Kong (CUHK-CMSCTRC).

DISCUSSION

The results of this study will establish comprehensive clinical evidence about the efficacy and safety of the Orthopaedic Manipulation Techniques of the Lin School of Lingnan Region in the Treatment of Adolescent Idiopathic Scoliosis. One of the characteristics of this trial is that it is a participant-and-assessor-blinded randomized controlled clinical trial with sham manipulation. The study would also apply three-dimensional (3D) ultrasound technology to investigate the relationship between the change of the muscle volume and the spinal curve.

TRIAL REGISTRATION

The trial is registered on ClinicalTrials.gov (Identifier: NCT05639023 ) on December 6, 2022.

Chiropractic spinal manipulative therapy for acute neck pain: A 4-arm clinical placebo randomized controlled trial. A prospective study protocol

INTRODUCTION

Neck pain poses enormous individual and societal costs worldwide. Spinal manipulative therapy and Non-Steroidal Anti-Inflammatory Drug treatment are frequently used despite a lack of compelling efficacy data. This protocol describes a multicentre 4-arm, clinical placebo randomized controlled trial (RCT), investigating the efficacy of chiropractic spinal manipulative therapy (CSMT) versus sham CSMT, ibuprofen, and placebo medicine for acute neck pain. This superiority study will employ parallel groups, featuring a 1:1:1:1 allocation ratio.

MATERIAL AND METHODS

We will randomize 320 participants equally into four groups: CSMT, sham CSMT, ibuprofen, or placebo medicine. CSMT groups are single-blinded, while the medicine groups are double-blinded. Data will be collected at baseline (Day 0), during treatment and post-treatment. The primary endpoint will assess the difference in mean pain intensity from Day 0 to Day 14 on a numeric rating scale 0-10; the CSMT group is compared to sham CSMT, ibuprofen, and placebo medicine groups, respectively. Secondary endpoints will assess mean pain intensity and mean duration at different time points, and adverse events, blinding success, and treatment satisfaction, including comparison between ibuprofen and placebo medicine. Power calculation is based on a mean neck pain rating of 5 at Day 0, with standard deviation of 1 in all groups. Mean pain reduction at Day 14 is expected to be 60% in the CSMT group, 40% in sham CSMT and ibuprofen groups, and 20% in the placebo medicine group. A linear mixed model will compare the mean values for groups with corresponding 95% confidence intervals. P values below 0.017 will be considered statistically significant. All analyses will be conducted blinded from group allocation.

DISCUSSION

This RCT aims towards the highest research standards possible for manual-therapy RCTs owing to its two placebo arms. If CSMT and/or ibuprofen proves to be effective, it will provide evidence-based support for CSMT and/or ibuprofen for acute neck pain.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT05374057. EU Clinical Trials Register: EudraCT number: 2021-005483-21.

Potential effect modifiers for treatment with chiropractic manipulation versus sham manipulation for recurrent headaches in children aged 7-14 years: development of and results from a secondary analysis of a randomised clinical trial

BACKGROUND

A recent randomized controlled trial (RCT) investigating the effect of chiropractic manipulation in 199 children aged 7-14 years with recurrent headaches demonstrated a significant reduction of number of days with headache and a better global perceived effect (GPE) in the chiropractic manipulation group compared to a sham manipulation group. However, potential modifiers for the effectiveness of chiropractic manipulation of children with recurrent headaches have never been identified. The present study is a secondary analysis of data from that RCT and will investigate potential effect modifiers for the benefit of chiropractic manipulation for children with headache.

METHODS

Sixteen potential effect modifiers were identified from the literature and a summary index was prespecified based on clinical experience. Relevant variables were extracted from baseline questionnaires, and outcomes were obtained by means of short text messages. The modifying effect of the candidate variables was assessed by fitting interaction models to the data of the RCT. In addition, an attempt to define a new summary index was made.

RESULTS

The prespecified index showed no modifying effect. Four single variables demonstrated a treatment effect difference of more than 1 day with headache per week between the lower and the upper end of the spectrum: intensity of headache (p = 0.122), Frequency of headache (p = 0.031), sleep duration (p = 0.243), and Socioeconomic status (p = 0.082). Five variables had a treatment effect difference of more than 0.7 points on the GPE scale between the lower and the upper end of the spectrum: Frequency of headache (p = 0.056), Sport activity (p = 0.110), Sleep duration (p = 0.080), History of neck pain (p = 0.011), and Headache in the family (0.050). A new summary index could be constructed giving highest weight to History of neck pain and Headache in the family and Frequency of headache. The index suggests a difference of about 1 point in GPE between low and high values of the index.

CONCLUSION

Chiropractic manipulation offers a moderate benefit for a broad spectrum of children. However, it cannot be excluded that specific headache characteristics, family factors, or a history of neck pain may modify the effect. This question must be addressed in future studies.

TRIAL REGISTRATION

ClinicalTrials.gov (Albers et al in Curr Pain Headache Rep 19:3-4, 2015), identifier NCT02684916, registered 02/18/2016-retrospectively registered.

Blinding and sham control methods in trials of physical, psychological, and self-management interventions for pain (article II): a meta-analysis relating methods to trial results

ABSTRACT

Sham interventions in randomized clinical trials (RCTs) of physical, psychological, and self-management (PPS) therapies for pain are highly variable in design and believed to contribute to poor internal validity. However, it has not been formally tested whether the extent to which sham controls resemble the treatment under investigation consistently affects trial outcomes, such as effect sizes, differential attrition, participant expectancy, and blinding effectiveness. Placebo- or sham-controlled RCTs of PPS interventions of clinical pain populations were searched in 12 databases. The similarity of control interventions to the experimental treatment was rated across 25 features. Meta-regression analyses assessed putative links between employed control interventions, observed effect sizes in pain-related outcomes, attrition, and blinding success. The sample included 198 unique control interventions, dominated by manual therapy and chronic musculoskeletal pain research. Meta-analyses indicated small-to-moderate benefits of active treatments over control interventions, across subgroups of manual therapies, exercise, and rehabilitation, and psychological intervention trials. Multiple meta-regression modelling demonstrated that similarity between sham control and tested interventions predicted variability in pain-related outcomes, attrition, and blinding effectiveness. Influential variables were differences relating to the extent of intervention exposure, participant experience, and treatment environments. The results support the supposed link between blinding methods and effect sizes, based on a large and systematically sourced overview of methods. However, challenges to effective blinding are complex and often difficult to discern from trial reports. Nonetheless, these insights have the potential to change trial design, conduct, and reporting and will inform guideline development.

Blinding and sham control methods in trials of physical, psychological, and self-management interventions for pain (article I): a systematic review and description of methods

ABSTRACT

Blinding is challenging in randomised controlled trials of physical, psychological, and self-management therapies for pain, mainly because of their complex and participatory nature. To develop standards for the design, implementation, and reporting of control interventions in efficacy and mechanistic trials, a systematic overview of currently used sham interventions and other blinding methods was required. Twelve databases were searched for placebo or sham-controlled randomised clinical trials of physical, psychological, and self-management treatments in a clinical pain population. Screening and data extraction were performed in duplicate, and trial features, description of control methods, and their similarity to the active intervention under investigation were extracted (protocol registration ID: CRD42020206590). The review included 198 unique control interventions, published between 2008 and December 2021. Most trials studied people with chronic pain, and more than half were manual therapy trials. The described control interventions ranged from clearly modelled based on the active treatment to largely dissimilar control interventions. Similarity between control and active interventions was more frequent for certain aspects (eg, duration and frequency of treatments) than others (eg, physical treatment procedures and patient sensory experiences). We also provide an overview of additional, potentially useful methods to enhance blinding, as well as the reporting of processes involved in developing control interventions. A comprehensive picture of prevalent blinding methods is provided, including a detailed assessment of the resemblance between active and control interventions. These findings can inform future developments of control interventions in efficacy and mechanistic trials and best-practice recommendations.

Mechanisms of chiropractic spinal manipulative therapy for patients with chronic primary low back pain: protocol for a mechanistic randomised placebo-controlled trial

INTRODUCTION

Chronic low back pain (CLBP) is a highly prevalent and disabling condition. Identifying subgroups of patients afflicted with CLBP is a current research priority, for which a classification system based on pain mechanisms was proposed. Spinal manipulative therapy (SMT) is recommended for the management of CLBP. Yet, little data are available regarding its mechanisms of action, making it difficult to match this intervention to the patients who may benefit the most. It was suggested that SMT may influence mechanisms associated with central sensitisation. Therefore, classifying patients with CLBP according to central sensitisation mechanisms may help predict their response to SMT.

METHODS AND ANALYSIS

This protocol describes a randomised placebo-controlled trial aiming to examine which variables linked to central sensitisation may help predict the clinical response to SMT in a cohort of patients with CLBP. One hundred patients with chronic primary low back pain will be randomised to receive 12 sessions of SMT or placebo SMT over a 4-week period. Pain intensity and disability will be assessed as primary outcomes after completing the 4-week treatment (primary endpoint), and at 4-week and 12-week follow-ups. Baseline values of two pain questionnaires, lumbar pressure pain thresholds, concentrations of an inflammatory cytokine and expectations of pain relief will be entered as predictors of the response to SMT in a multiple regression model. Changes in these variables after treatment will be used in a second multiple regression model. The reference values of these predictors will be measured from 50 age and sex-matched healthy controls to allow interpretation of values in patients. Mixed analyses of variance will also be conducted to compare the primary outcomes and the predictors between groups (SMT vs placebo) over time (baseline vs post-treatment).

ETHICS AND DISSEMINATION

Ethical approval was granted by the Fundación Jiménez Díaz Clinical Research Ethics Committee.

TRIAL REGISTRATION NUMBER

NCT05162924.

Manual Therapy Effect in Placebo-Controlled Trials: A Systematic Review and Meta-Analysis

PURPOSE

Background: Evaluate whether the design of placebo control groups could produce different interpretations of the efficacy of manual therapy techniques.

METHODS

Nine databases were searched (EMBASE, CINAHL, PsycINFO, MEDLINE, PubMed, SCOPUS, WEB of SCIENCE, COCHRANE, and PEDro). Randomized placebo-controlled clinical trials that used manual therapy as a sham treatment on subjects suffering from pain were included. Data were summarized qualitatively, and meta-analyses were conducted with R.

RESULTS

53 articles were included in the qualitative analysis and 48 were included in the quantitative analyses. Manipulation techniques did not show higher effectiveness when compared with all types of sham groups that were analyzed (SMD 0.28; 95%CI [-0.24; 0.80]) (SMD 0.28; 95%CI [-0.08; 0.64]) (SMD 0.42; 95%CI [0.16; 0.67]) (SMD 0.82; 95%CI [-0.57; 2.21]), raising doubts on their therapeutic effect. Factors such as expectations of treatment were not consistently evaluated, and analysis could help clarify the effect of different sham groups. As for soft tissue techniques, the results are stronger in favor of these techniques when compared to sham control groups (SMD 0.40; 95%CI [0.19, 0.61]). Regarding mobilization techniques and neural gliding techniques, not enough studies were found for conclusions to be made.

CONCLUSIONS

The literature presents a lack of a unified placebo control group design for each technique and an absence of assessment of expectations. These two issues might account for the unclear results obtained in the analysis.

Differences between experimental and placebo arms in manual therapy trials: a methodological review

BACKGROUND

To measure the specific effectiveness of a given treatment in a randomised controlled trial, the intervention and control groups have to be similar in all factors not distinctive to the experimental treatment. The similarity of these non-specific factors can be defined as an equality assumption. The purpose of this review was to evaluate the equality assumptions in manual therapy trials.

METHODS

Relevant studies were identified through the following databases: EMBASE, MEDLINE, SCOPUS, WEB OF SCIENCE, Scholar Google, clinicaltrial.gov, the Cochrane Library, chiloras/MANTIS, PubMed Europe, Allied and Complementary Medicine (AMED), Physiotherapy Evidence Database (PEDro) and Sciencedirect. Studies investigating the effect of any manual intervention compared to at least one type of manual control were included. Data extraction and qualitative assessment were carried out independently by four reviewers, and the summary of results was reported following the PRISMA statement.

RESULT

Out of 108,903 retrieved studies, 311, enrolling a total of 17,308 patients, were included and divided into eight manual therapy trials categories. Equality assumption elements were grouped in three macro areas: patient-related, context-related and practitioner-related items. Results showed good quality in the reporting of context-related equality assumption items, potentially because largely included in pre-existent guidelines. There was a general lack of attention to the patient- and practitioner-related equality assumption items.

CONCLUSION

Our results showed that the similarity between experimental and sham interventions is limited, affecting, therefore, the strength of the evidence. Based on the results, methodological aspects for planning future trials were discussed and recommendations to control for equality assumption were provided.

Efficacy of contralateral acupuncture in women with migraine without aura: protocol for a randomised controlled trial

INTRODUCTION

Migraine is a common neurological disorder with a higher prevalence occurring in women. Migraine without aura (MwoA) is the most common type of migraine. In recent years, the safety and effectiveness of acupuncture for migraines have been internationally recognised. Contralateral acupuncture (CAT) (Jùcì) is an ancient classic acupuncture technique from Huang Di Nei Jing that refers to the acupoints on the right side (healthy side) selected for diseases on the left (affected side) and vice versa. Some studies have shown that efficacy of CAT on the painful disorder is even better than ipsilateral acupuncture (IAT), but there remains a lack of high-quality evidence to support it.

METHODS AND ANALYSIS

This is a single-centre, randomised and sham-controlled clinical trial in China with three parallel groups that aim to evaluate the efficacy of CAT in women with unilateral MwoA. 243 participants will be randomly divided into the experimental group (CAT group), control group 1 (IAT group) and control group 2 (sham acupuncture group) (1:1:1 allocation ratio). Each group will be given 30-minute treatment sessions, once every other day, approximately three times per week, for a total of 24 treatments and follow-up visits two times. The primary outcome is the changes in days of migraine attacks. The secondary outcomes are frequency of migraine attacks, intensity of migraine, migraine duration, the dose of intake of acute medication, the Migraine-Specific Quality of Life Questionnaire, the Migraine Disability Assessment Score, the Headache Impact Test-6 and the Pittsburgh Sleep Quality Index. The data will be collected at the baseline time (week 0), end of treatment (week 4-8) and the follow-up time (week 12-16). Adverse events will be collected and recorded during each treatment.

ETHICS AND DISSEMINATION

Ethics approval was obtained from the Ethics Committee of the Sports Trauma Specialist Hospital of Yunnan Province (2021-01). All participants will provide written informed consent before randomisation. The results of this study will be published in a peer-reviewed journal and presented at conferences.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registration Center (ChiCTR2100051479).

Feasibility of Using Detuned Laser as a Placebo In Manual Therapy Research: An Analysis of Participant Perceptions

OBJECTIVE

The purpose of this study was to determine the feasibility of using detuned laser as a placebo intervention in manual therapy research.

METHODS

We performed a secondary data analysis of a randomized controlled trial. In our analysis, 30 participants with chronic ankle instability (manual therapy group: n = 13, age = 33.1 ± 8.1 years, female participants = 50%; detuned laser group: n = 17, age = 31.9 ± 11.8 years, female participants = 72%) were asked to indicate which intervention (manual therapy [active] or detuned laser [placebo]), they thought they had received and to give a confidence rating on their response regarding the received intervention at the conclusion of the course of intervention. Independent t tests were used to compare the groups. Participants in both groups were asked the following open-ended question: "What did you think of the intervention?".

RESULTS

There were 52.9% participants in the detuned laser group and 53.8% participants in the manual therapy group who perceived that they had received the active intervention. The confidence ratings about their perceptions (6.7 ± 2.0, detuned laser group; 6.3 ± 2.4, manual therapy group) (P = .66) and the self-reported recovery ratings (1.9 ± 1.5 and 1.8 ± 1.2, respectively) (P = .77) were similar.

CONCLUSIONS

Participants in this study confidently perceived that detuned laser was an active intervention. They positively rated their recovery following the course of the placebo intervention and perceived that detuned laser was effective in treating their condition. Therefore, it is feasible for detuned laser to be used as a placebo for manual therapy trials.

Immediate effects of spinal manipulation on painful sensitivity and postural stability in patients with chronic nonspecific low back pain: study protocol for a controlled randomised clinical trial

BACKGROUND

Low back pain is one of the main public health concerns. Chronic low back pain (cLBP) reduces functional capacity and affects postural stability. Although health professionals widely use spinal manipulation, its immediate effect on painful sensitivity and postural stability is lacking. This study aims to verify the immediate effects of lumbar spinal manipulation on the pressure pain threshold and postural stability in individuals with cLBP.

METHODS

A two-arm, placebo-controlled clinical trial with parallel groups and examiner-blinded will be conducted with 80 participants with cLBP from an outpatient physical therapy department, randomly allocated at a 1:1 distribution. The experimental group will receive a lumbar spinal manipulation technique, and the placebo group will receive a simulated lumbar spinal manipulation. Both groups will receive one session of treatment and will be evaluated before and immediately after the intervention. The primary outcomes will be the pressure pain threshold and postural stability. Pain intensity and patient's expectation will be assessed as a secondary outcome. The pressure pain threshold will be assessed using a pressure algometer in 6 different anatomical regions. The evaluation of postural stability will be performed in a baropodometry exam by displacing the centre of pressure. The pain intensity will be measured using the Numeric Pain Rating Scale. A Likert scale will be used for the patient's expectation about the treatment. A two-way analysis of variance will compare the effect of the interventions between groups.

DISCUSSION

This study will provide insights regarding the immediate effects of spinal manipulation in patients with cLBP against a simulated spinal manipulation using objective outcomes and considering patients' expectations regarding the treatment.

TRIAL REGISTRATION

Brazilian Registry of Clinical Trials RBR-3ksq2c . Registered on 13 July 2020.

Segmental Chiropractic Spinal Manipulation Does not Reduce Pain Amplification and the Associated Pain-Related Brain Activity in a Capsaicin-Heat Pain Model

Musculoskeletal injuries lead to sensitization of nociceptors and primary hyperalgesia (hypersensitivity to painful stimuli). This occurs with back injuries, which are associated with acute pain and increased pain sensitivity at the site of injury. In some cases, back pain persists and leads to central sensitization and chronic pain. Thus, reducing primary hyperalgesia to prevent central sensitization may limit the transition from acute to chronic back pain. It has been shown that spinal manipulation (SM) reduces experimental and clinical pain, but the effect of SM on primary hyperalgesia and hypersensitivity to painful stimuli remains unclear. The goal of the present study was to investigate the effect of SM on pain hypersensitivity using a capsaicin-heat pain model. Laser stimulation was used to evoke heat pain and the associated brain activity, which were measured to assess their modulation by SM. Eighty healthy participants were recruited and randomly assigned to one of the four experimental groups: inert cream and no intervention; capsaicin cream and no intervention; capsaicin cream and SM at T7; capsaicin cream and placebo. Inert or capsaicin cream (1%) was applied to the T9 area. SM or placebo were performed 25 min after cream application. A series of laser stimuli were delivered on the area of cream application (1) before cream application, (2) after cream application but before SM or placebo, and (3) after SM or placebo. Capsaicin cream induced a significant increase in laser pain (p < 0.001) and laser-evoked potential amplitude (p < 0.001). However, SM did not decrease the amplification of laser pain or laser-evoked potentials by capsaicin. These results indicate that segmental SM does not reduce pain hypersensitivity and the associated pain-related brain activity in a capsaicin-heat pain model.

Spinal Manipulative Therapy for Acute Neck Pain: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

(1) Background: Acute neck pain is common and usually managed by medication and/or manual therapy. General practitioners (GPs) hesitate to refer to manual therapy due to uncertainty about the effectiveness and adverse events (AEs); (2) Method: To review original randomized controlled trials (RCTs) assessing the effect of spinal manipulative therapy (SMT) for acute neck pain. Data extraction was done in duplicate and formulated in tables. Quality and evidence were assessed using the Cochrane Back and Neck (CBN) Risk of Bias tool and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria, respectively; (3) Results: Six studies were included. The overall pooled effect size for neck pain was very large −1.37 (95% CI, −2.41, −0.34), favouring treatments with SMT compared with controls. A single study that showed that SMT was statistically significantly better than medicine (30 mg ketorolac im.) one day post-treatment, ((−2.8 (46%) (95% CI, −2.1, −3.4) vs. −1.7 (30%) (95% CI, −1.1, −2.3), respectively; p = 0.02)). Minor transient AEs reported included increased pain and headache, while no serious AEs were reported; (4) Conclusions: SMT alone or in combination with other modalities was effective for patients with acute neck pain. However, limited quantity and quality, pragmatic design, and high heterogeneity limit our findings.

Clinical Effectiveness and Efficacy of Chiropractic Spinal Manipulation for Spine Pain

Spine pain is a highly prevalent condition affecting over 11% of the world's population. It is the single leading cause of activity limitation and ranks fourth in years lost to disability globally, representing a significant personal, social, and economic burden. For the vast majority of patients with back and neck pain, a specific pathology cannot be identified as the cause for their pain, which is then labeled as non-specific. In a growing proportion of these cases, pain persists beyond 3 months and is referred to as chronic primary back or neck pain. To decrease the global burden of spine pain, current data suggest that a conservative approach may be preferable. One of the conservative management options available is spinal manipulative therapy (SMT), the main intervention used by chiropractors and other manual therapists. The aim of this narrative review is to highlight the most relevant and up-to-date evidence on the effectiveness (as it compares to other interventions in more pragmatic settings) and efficacy (as it compares to inactive controls under highly controlled conditions) of SMT for the management of neck pain and low back pain. Additionally, a perspective on the current recommendations on SMT for spine pain and the needs for future research will be provided. In summary, SMT may be as effective as other recommended therapies for the management of non-specific and chronic primary spine pain, including standard medical care or physical therapy. Currently, SMT is recommended in combination with exercise for neck pain as part of a multimodal approach. It may also be recommended as a frontline intervention for low back pain. Despite some remaining discrepancies, current clinical practice guidelines almost universally recommend the use of SMT for spine pain. Due to the low quality of evidence, the efficacy of SMT compared with a placebo or no treatment remains uncertain. Therefore, future research is needed to clarify the specific effects of SMT to further validate this intervention. In addition, factors that predict these effects remain to be determined to target patients who are more likely to obtain positive outcomes from SMT.

Manual therapy in adults with tension-type headache: A systematic review

INTRODUCTION

Tension-type headache is the most common primary headache, with a high prevalence and a considerable socioeconomic impact. Manual physical therapy techniques are widely used in the clinical field to treat the symptoms associated with tension-type headache. This systematic review aims to determine the effectiveness of manual and non-invasive therapies in the treatment of patients with tension-type headache.

DEVELOPMENT

We conducted a systematic review of randomised controlled trials in the following databases: Brain, PubMed, Web of Science, PEDro, Scopus, CINAHL, and Science Direct. Ten randomised controlled trials were included for analysis. According to these studies, manual therapy improves symptoms, increasing patients' well-being and improving the outcome measures analysed.

CONCLUSIONS

Manual therapy has positive effects on pain intensity, pain frequency, disability, overall impact, quality of life, and craniocervical range of motion in adults with tension-type headache. None of the techniques was found to be superior to the others; combining different techniques seems to be the most effective approach.

Validation of a sham novel neural mobilization technique in patients with non-specific low back pain: A randomized, placebo-controlled trial

BACKGROUND

There is no validated sham neural mobilization (NM) intervention for lower quadrant conditions. A suitable sham NM comparator will allow to blind patients with low back pain (LBP) and reduce bias by limiting the confounding effects of expectations.

OBJECTIVE

The primary aim was to develop a sham NM technique in patients with non-specific LBP and assess its validity in supplying a suitable blinding. Secondly, we compared the short-term effects of NM and the sham comparator on pain and the straight leg raise.

DESIGN

A randomized placebo-controlled trial in which participants and assessors were blinded.

METHOD

Fifty one patients (20 men,31 women), aged 22-65 years (43 ± 12y) were allocated randomly to a NM group (n = 26) or a sham NM group (n = 25). The primary outcome of believability of the sham technique was measured one week after the intervention. Secondary outcomes of pain intensity and the straight leg raise range-of-motion were assessed at baseline, immediately after the intervention and one week after.

RESULTS

The believability of the sham technique in terms of the frequencies of perceived group assignment showed no differences between groups. Eighteen participants believed they had received the experimental NM technique in the experimental group (69.2%) and 14 in the placebo NM group (56%). Pain and the straight leg raise changes did not show differences between groups.

CONCLUSIONS

The novel sham NM demonstrated to be a believable intervention, capable of supplying a suitable blinding. Both groups showed similar short term perceived effects on pain and the straight leg raise.

The Effects of 4 Weeks of Chiropractic Spinal Adjustments on Motor Function in People with Stroke: A Randomized Controlled Trial

Chiropractic spinal adjustments have been shown to result in short-term increases in muscle strength in chronic stroke patients, however, the effect of longer-term chiropractic spinal adjustments on people with chronic stroke is unknown. This exploratory study assessed whether 4 weeks of chiropractic spinal adjustments, combined with physical therapy (chiro + PT), had a greater impact than sham chiropractic with physical therapy (sham + PT) did on motor function (Fugl Meyer Assessment, FMA) in 63 subacute or chronic stroke patients. Secondary outcomes included health-related quality of life and other measures of functional mobility and disability. Outcomes were assessed at baseline, 4 weeks (post-intervention), and 8 weeks (follow-up). Data were analyzed using linear mixed-effects models or generalized linear mixed models. A post-hoc responder analysis was performed to investigate the clinical significance of findings. At 4 weeks, there was a larger effect of chiro + PT, compared with sham + PT, on the FMA (difference = 6.1, p = 0.04). The responder analysis suggested the improvements in motor function seen following chiropractic spinal adjustments may have been clinically significant. There was also a robust improvement in both groups in most measures from baseline to the 4- and 8-week assessments, but between-group differences were no longer significant at the 8-week assessment. Four weeks of chiro + PT resulted in statistically significant improvements in motor function, compared with sham + PT, in people with subacute or chronic stroke. These improvements appear to be clinically important. Further trials, involving larger group sizes and longer follow-up and intervention periods, are required to corroborate these findings and further investigate the impacts of chiropractic spinal adjustments on motor function in post-stroke survivors. ClinicalTrials.gov Identifier NCT03849794.

Sham treatment effects in manual therapy trials on back pain patients: a systematic review and pairwise meta-analysis

OBJECTIVE

To assess the effects and reliability of sham procedures in manual therapy (MT) trials in the treatment of back pain (BP) in order to provide methodological guidance for clinical trial development.

DESIGN

Systematic review and meta-analysis.

METHODS AND ANALYSIS

Different databases were screened up to 20 August 2020. Randomised controlled trials involving adults affected by BP (cervical and lumbar), acute or chronic, were included.Hand contact sham treatment (ST) was compared with different MT (physiotherapy, chiropractic, osteopathy, massage, kinesiology and reflexology) and to no treatment. Primary outcomes were BP improvement, success of blinding and adverse effect (AE). Secondary outcomes were number of drop-outs. Dichotomous outcomes were analysed using risk ratio (RR), continuous using mean difference (MD), 95% CIs. The minimal clinically important difference was 30 mm changes in pain score.

RESULTS

24 trials were included involving 2019 participants. Very low evidence quality suggests clinically insignificant pain improvement in favour of MT compared with ST (MD 3.86, 95% CI 3.29 to 4.43) and no differences between ST and no treatment (MD -5.84, 95% CI -20.46 to 8.78).ST reliability shows a high percentage of correct detection by participants (ranged from 46.7% to 83.5%), spinal manipulation being the most recognised technique.Low quality of evidence suggests that AE and drop-out rates were similar between ST and MT (RR AE=0.84, 95% CI 0.55 to 1.28, RR drop-outs=0.98, 95% CI 0.77 to 1.25). A similar drop-out rate was reported for no treatment (RR=0.82, 95% 0.43 to 1.55).

CONCLUSIONS

MT does not seem to have clinically relevant effect compared with ST. Similar effects were found with no treatment. The heterogeneousness of sham MT studies and the very low quality of evidence render uncertain these review findings.Future trials should develop reliable kinds of ST, similar to active treatment, to ensure participant blinding and to guarantee a proper sample size for the reliable detection of clinically meaningful treatment effects.

PROSPERO REGISTRATION NUMBER

CRD42020198301.

Neurophysiological mechanisms of chiropractic spinal manipulation for spine pain

Together, neck pain and back pain are the first cause of disability worldwide, accounting for more than 10% of the total years lived with disability. In this context, chiropractic care provides a safe and effective option for the management of a large proportion of these patients. Chiropractic is a healthcare profession mainly focused on the spine and the treatment of spinal disorders, including spine pain. Basic studies have examined the influence of chiropractic spinal manipulation (SM) on a variety of peripheral, spinal and supraspinal mechanisms involved in spine pain. While spinal cord mechanisms of pain inhibition contribute at least partly to the pain-relieving effects of chiropractic treatments, the evidence is weaker regarding peripheral and supraspinal mechanisms, which are important components of acute and chronic pain. This narrative review highlights the most relevant mechanisms of pain relief by SM and provides a perspective for future research on SM and spine pain, including the validation of placebo interventions that control for placebo effects and other non-specific effects that may be induced by SM. SIGNIFICANCE: Spinal manipulation inhibits back and neck pain partly through spinal segmental mechanisms and potentially through peripheral mechanisms regulating inflammatory responses. Other mechanisms remain to be clarified. Controls and placebo interventions need to be improved in order to clarify the contribution of specific and non-specific effects to pain relief by spinal manipulative therapy.

Is the N-of-1 method applicable in bodywork research? Lessons learned using a trial as a methodological pilot

N-of-1 trial designs have rarely been used in bodywork research. Using a recent trial as a methodological pilot, critical issues related to the applicability of N-of-1 trials to bodywork are discussed. These include the issues of carry-over effects, bias-controlling approaches and statistical analysis. The discussion highlights the importance of mixed methods and draws some suggestions for a future research program. N-of-1 trials could be used to provide insights about some essential elements of bodywork modalities and their effectiveness.

Effectiveness of chiropractic manipulation versus sham manipulation for recurrent headaches in children aged 7-14 years - a randomised clinical trial

Background

To investigate the effectiveness of chiropractic spinal manipulation versus sham manipulation in children aged 7–14 with recurrent headaches.

Methods

Design: A two-arm, single-blind, superiority randomised controlled trial.

Setting: One chiropractic clinic and one paediatric specialty practice in Denmark, November 2015 to August 2020.

Participants: 199 children aged 7 to 14 years, with at least one episode of headache per week for the previous 6 months and at least one musculoskeletal dysfunction identified.

Interventions: All participants received standard oral and written advice to reduce headaches. In addition, children in the active treatment group received chiropractic spinal manipulation and children in the control group received sham manipulation for a period of 4 months. Number and frequency of treatments were based on the chiropractor’s individual evaluation in the active treatment group; the children in the control group received approximately eight visits during the treatment period.

Primary outcome measures: ‘Number of days with headache’, ‘pain intensity’ and ‘medication’ were reported weekly by text messages, and global perceived effect by text message after 4 months. A planned fixed sequence strategy based on an initial outcome data analysis was used to prioritize outcomes. ‘Number of days with headache’ and ‘pain intensity’ were chosen as equally important outcomes of highest priority, followed by global perceived effect and medication. The significance level for the first two outcomes was fixed to 0.025 to take multiplicity into account.

Results

Chiropractic spinal manipulation resulted in significantly fewer days with headaches (reduction of 0.81 vs. 0.41, p = 0.019, NNT = 7 for 20% improvement) and better global perceived effect (dichotomized into improved/not improved, OR = 2.8 (95% CI: 1.5–5.3), NNT = 5) compared with a sham manipulation procedure. There was no difference between groups for pain intensity during headache episodes. Due to methodological shortcomings, no conclusions could be drawn about medication use.

Conclusions

Chiropractic spinal manipulation resulted in fewer headaches and higher global perceived effect, with only minor side effects. It did not lower the intensity of the headaches.

Since the treatment is easily applicable, of low cost and minor side effects, chiropractic spinal manipulation might be considered as a valuable treatment option for children with recurrent headaches.

Trial registration

ClinicalTrials.gov, identifier NCT02684916, registered 02/18/2016 – retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12998-020-00360-3.

Brain Connectivity Changes after Osteopathic Manipulative Treatment: A Randomized Manual Placebo-Controlled Trial

The effects of osteopathic manipulative treatment (OMT) on functional brain connectivity in healthy adults is missing in the literature. To make up for this lack, we applied advanced network analysis methods to analyze resting state functional magnetic resonance imaging (fMRI) data, after OMT and Placebo treatment (P) in 30 healthy asymptomatic young participants randomized into OMT and placebo groups (OMTg; Pg). fMRI brain activity measures, performed before (T0), immediately after (T1) and three days after (T2) OMT or P were used for inferring treatment effects on brain circuit functional organization. Repeated measures ANOVA and post-hoc analysis demonstrated that Right Precentral Gyrus (F (2, 32) = 5.995, p < 0.005) was more influential over the information flow immediately after the OMT, while decreased betweenness centrality in Left Caudate (F (2, 32) = 6.496, p < 0.005) was observable three days after. Clustering coefficient showed a distinct time-point and group effect. At T1, reduced neighborhood connectivity was observed after OMT in the Left Amygdala (L-Amyg) (F (2, 32) = 7.269, p < 0.005) and Left Middle Temporal Gyrus (F (2, 32) = 6.452, p < 0.005), whereas at T2 the L-Amyg and Vermis-III (F (2, 32) = 6.772, p < 0.005) increased functional interactions. Data demonstrated functional connectivity re-arrangement after OMT.

The Effect of Spinal Manipulation on the Electrophysiological and Metabolic Properties of the Tibialis Anterior Muscle

There is growing evidence showing that spinal manipulation increases muscle strength in healthy individuals as well as in people with some musculoskeletal and neurological disorders. However, the underlying mechanism by which spinal manipulation changes muscle strength is less clear. This study aimed to assess the effects of a single spinal manipulation session on the electrophysiological and metabolic properties of the tibialis anterior (TA) muscle. Maximum voluntary contractions (MVC) of the ankle dorsiflexors, high-density electromyography (HDsEMG), intramuscular EMG, and near-infrared spectroscopy (NIRS) were recorded from the TA muscle in 25 participants with low level recurring spinal dysfunction using a randomized controlled crossover design. The following outcomes: motor unit discharge rate (MUDR), strength (force at MVC), muscle conduction velocity (CV), relative changes in oxy- and deoxyhemoglobin were assessed pre and post a spinal manipulation intervention and passive movement control. Repeated measures ANOVA was used to assess within and between-group differences. Following the spinal manipulation intervention, there was a significant increase in MVC (p = 0.02; avg 18.87 ± 28.35%) and a significant increase in CV in both the isometric steady-state (10% of MVC) contractions (p < 0.01; avg 22.11 ± 11.69%) and during the isometric ramp (10% of MVC) contractions (p < 0.01; avg 4.52 ± 4.58%) compared to the control intervention. There were no other significant findings. The observed TA strength and CV increase, without changes in MUDR, suggests that the strength changes observed following spinal manipulation are, in part, due to increased recruitment of larger, higher threshold motor units. Further research needs to investigate the longer term and potential functional effects of spinal manipulation in various patients who may benefit from improved muscle function and greater motor unit recruitment.

Sample size, study length, and inadequate controls were the most common self-acknowledged limitations in manual therapy trials: A methodological review

OBJECTIVES

The aim of this study was to quantify and analyze the presence and type of self-acknowledged limitations (SALs) in a sample of manual therapy (MT) randomized controlled trials.

STUDY DESIGN AND SETTING

We randomly selected 120 MT trials. We extracted data related to SALs from the original reports and classified them into 12 categories. After data extraction, specific limitations within each category were identified. A descriptive analysis was performed using frequencies and percentages for qualitative variables.

RESULTS

The number of SALs per trial article ranged from 0 to 8, and more than two-thirds of trials acknowledged at least two different limitations. Despite its small proportion, 9% of trials did not report SALs. The most common limitation declared, in almost half of our sample, related to sample size (47.5%) followed by limitations related to study length and follow-up (33.3%) and inadequate controls (32.5%).

CONCLUSION

Our results indicate that at least two different limitations are consistently acknowledged in MT trial reports, the most common being those related to sample size, study length, follow-up, and inadequate controls. Analysis of the reasons behind the SALs gives some insights about the main difficulties in conducting research in this field and may help develop strategies to improve future research.

Context matters: the psychoneurobiological determinants of placebo, nocebo and context-related effects in physiotherapy

Background

Placebo and nocebo effects embody psychoneurobiological phenomena where behavioural, neurophysiological, perceptive and cognitive changes occur during the therapeutic encounter in the healthcare context. Placebo effects are produced by a positive healthcare context; while nocebo effects are consequences of negative healthcare context. Historically, placebo, nocebo and context-related effects were considered as confounding elements for clinicians and researchers. In the last two decades this attitude started to change, and the understanding of the value of these effects has increased. Despite the growing interest, the knowledge and the awareness of using the healthcare context to trigger placebo and nocebo effects is currently limited and heterogeneous among physiotherapists, reducing their translational value in the physiotherapy field.

Objectives

To introduce the placebo, nocebo and context-related effects by: (1) presenting their psychological models; (2) describing their neurophysiological mechanisms; (3) underlining their impact for the physiotherapy profession; and (4) tracing lines for future researches.

Conclusion

Several psychological mechanisms are involved in placebo, nocebo and context-related effects; including expectation, learning processes (classical conditioning and observational learning), reinforced expectations, mindset and personality traits. The neurophysiological mechanisms mainly include the endogenous opioid, the endocannabinoid and the dopaminergic systems. Neuroimaging studies have identified different brain regions involved such as the dorsolateral prefrontal cortex, the rostral anterior cingulate cortex, the periaqueductal gray and the dorsal horn of spine. From a clinical perspective, the manipulation of the healthcare context with the best evidence-based therapy represents an opportunity to trigger placebo effects and to avoid nocebo effects respecting the ethical code of conduct. From a managerial perspective, stakeholders, organizations and governments should encourage the assessment of the healthcare context aimed to improve the quality of physiotherapy services. From an educational perspective, placebo and nocebo effects are professional topics that should be integrated in the university program of health and medical professions. From a research perspective, the control of placebo, nocebo and context-related effects offers to the scientific community the chance to better measure the impact of physiotherapy on different outcomes and in different conditions through primary studies.

Changes in pressure pain threshold and temporal summation in rapid responders and non-rapid responders after lumbar spinal manipulation and sham: A secondary analysis in adults with low back pain

BACKGROUND

People with LBP who experience rapid improvement in symptoms after spinal manipulative therapy (SMT) are more likely to experience better longer-term outcomes compared to those who don't improve rapidly. It is unknown if short-term hypoalgesia after SMT could be a relevant finding in rapid responders.

OBJECTIVES

We aimed to explore whether rapid responders had different short-term pressure pain threshold (PPT) and temporal summation (TS) outcomes after SMT and sham compared to non-rapid responders.

METHODS

This was a planned secondary analysis of a randomised controlled trial that recruited 80 adults with LBP (42 females, mean age 37 yrs). PPT at the calf, lumbar spine, and shoulder and TS at the hands and feet were measured before and three times over 30 min after a lumbar SMT or sham manipulation. Participants were classified as rapid responders or non-rapid responders based on self-reported change in LBP over the following 24 h.

RESULTS

Shoulder PPT transiently increased more in the rapid responders than non-rapid responders immediately post-intervention only (between-group difference in change from baseline = 0.29 kg/cm², 95% CI 0.02-0.56, p = .0497). There were no differences in calf PPT, lumbar PPT, hand TS, or foot TS based on responder status.

CONCLUSIONS

Hypoalgesia in shoulder PPT occurred transiently in the rapid responders compared to the non-rapid responders. This may or may not contribute to symptomatic improvement after SMT or sham in adults with LBP, and may be a spurious finding. Short-term changes in TS do not appear to be related to changes in LBP.

What is the effect of spinal manipulation on the pressure pain threshold in young, asymptomatic subjects? A randomized placebo-controlled trial, with a cross-over design

BACKGROUND

Spinal manipulation (SM) has been shown to have an effect on the pressure pain threshold (PPT) in asymptomatic subjects, but SM has never been compared in studies on this topic to a validated sham procedure. We investigated the effect of SM on the PPT when measured i) in the area of intervention and ii) in an area remote from the intervention. In addition, we measured the size and duration of the effect.

METHOD

In a randomized cross-over trial, 50 asymptomatic chiropractic students had their PPT measured at baseline, immediately after and every 12 min after intervention, over a period of 45 min, comparing values after SM and a previously validated sham. The trial was conducted during two sessions, separated by 48 h. PPT was measured both regionally and remotely from the 'treated' thoracic segment. Blinding of study subjects was tested with a post-intervention questionnaire. We used mixed linear regression with the baseline value and time as co-variates. If a significant difference were found between groups, then an effect size would be calculated using Cohen's d or Hedge's h coefficient. Statistical significance was set at p < 0.05.

RESULTS

Study subjects had been successfully blinded. No statistically significant differences were found between SM and sham estimates, at any time or anatomical location.

CONCLUSION

When compared to a valid sham procedure and with successfully blinded subjects, there is no regional or remote effect of spinal manipulation of the thoracic spine on the pressure pain threshold in a young pain-free population.

The effect of a single spinal manipulation on cardiovascular autonomic activity and the relationship to pressure pain threshold: a randomized, cross-over, sham-controlled trial

Background

The autonomic nervous system interacts with the pain system. Knowledge on the effects of high velocity low amplitude spinal manipulations (SM) on autonomic activity and experimentally induced pain is limited. In particular, the effects of SM on autonomic activity and pain beyond the immediate post intervention period as well as the relationship between these two outcomes are understudied. Thus, new research is needed to provide further insight on this issue.

Objectives

The aim was to assess the effect of a single SM (i.e. SM vs. sham) on cardiovascular autonomic activity. Also, we assessed the relationship between cardiovascular autonomic activity and level of pain threshold after the interventions.

Method

We conducted a randomized, cross-over, sham-controlled trial on healthy first-year chiropractic students comprising two experimental sessions separated by 48 h. During each session, subjects received, in a random order, either a thoracic SM or a sham manipulation. Cardiovascular autonomic activity was assessed using heart rate and systolic blood pressure variabilities. Pain sensitivity was assessed using pressure pain threshold. Measurements were performed at baseline and repeated three times (every 12 min) during the post intervention period. Participants and outcome assessors were blinded. The effect of the SM was tested with linear mixed models. The relationship between autonomic outcomes and pressure pain threshold was tested with bivariate correlations.

Results

Fifty-one participants were included, forty-one were finally analyzed. We found no statistically significant difference between SM and sham in cardiovascular autonomic activity post intervention. Similarly, we found no post-intervention relationship between cardiovascular autonomic activity and pressure pain threshold.

Conclusion

Our results suggest that a single SM of the thoracic spine has no specific effect on cardiovascular autonomic activity. Also, we found no relationship between cardiovascular autonomic activity and pressure pain threshold after the SM. Further experimental research should consider the use of several markers of autonomic activity and a more comprehensive pain assessment.

Trial registration

N° NCT03273868. Registered September 6, 2017.

Adding Chiropractic Treatment to Individual Rehabilitation for Persistent Pelvic Girdle Pain 3 to 6 Months After Delivery: A Pilot Randomized Trial

OBJECTIVE

The purpose of this study was to investigate the feasibility of conducting a study examining the influence of individualized rehabilitation and chiropractic treatment, compared with individualized rehabilitation alone, in women with persistent dominating 1-sided pelvic girdle pain (PGP) 3 to 6 months after delivery.

METHODS

Women were recruited from an outpatient clinic at Stavanger University Hospital, Norway and in a private chiropractic clinic in Stavanger. Those with persistent, dominating 1-sided PGP were included in this pilot study. Those who met inclusion criteria were randomized into 2 groups, one group received individualized rehabilitation and chiropractic treatment and the other group women received individualized rehabilitation alone. Treatment was measured for 20 weeks.

RESULTS

Of 330 consenting women who were recruited who reported pelvic pain during pregnancy, 68 reported PGP or low back pain, and 63 consented to fill in a questionnaire. Forty-seven women underwent a clinical examination 3 to 6 months after delivery. During the examination, the women were diagnosed into subgroups for PGP. After exclusion of the women with low back pain only, a total of 13 women were diagnosed with dominating 1-sided PGP and thus included in this study. Six were randomized to the individualized rehabilitation and chiropractic treatment group and 5 to the individualized rehabilitation alone group. After 20 weeks of intervention, both groups reported improvement in disability and pain, but not in general health status. No serious or long-lasting adverse events were registered after treatment or training.

CONCLUSION

We found that a study of this nature is feasible. However, the conditions of patient recruitment need to be considered carefully. We learned that a trial to investigate the effect of chiropractic treatment for PGP pain should include all subgroups of PGP to reach an acceptable sample size.

Blinding Strategies in Dry Needling Trials: Systematic Review and Meta-Analysis

BACKGROUND

Blinding of participants and therapists in trials of physical interventions is a significant and ongoing challenge. There is no widely accepted sham protocol for dry needling.

PURPOSE

The purpose of this review was to summarize the effectiveness and limitations of blinding strategies and types of shams that have been used in dry needling trials.

DATA SOURCES

Twelve databases were searched from inception to February 2016.

STUDY SELECTION

Trials that compared active dry needling with a sham that simulated dry needling were included.

DATA EXTRACTION

The main domains of data extraction were participant/therapist details, intervention details, blinding strategies, blinding assessment outcomes, and key conclusions of authors. Reported blinding strategies and sham types were synthesized descriptively, with available blinding effectiveness data synthesized using a chance-corrected measurement of blinding (blinding index).

DATA SYNTHESIS

The search identified 4894 individual publications with 27 trials eligible for inclusion. In 22 trials, risk of methodological bias was high or unclear. Across trials, blinding strategies and sham types were heterogeneous. Notably, no trials attempted therapist blinding. Sham protocols have focused on participant blinding using strategies related to group standardization and simulation of tactile sensations. There has been little attention given to the other senses or cognitive strategies to enhance intervention credibility. Nonpenetrating sham types may provide effective participant blinding.

LIMITATIONS

Trials were clinically and methodologically diverse, which limited the comparability of blinding effectiveness across trials. Reported blinding evaluations had a high risk of chance findings with power clearly achieved in only 1 trial.

CONCLUSIONS

Evidence-based consensus on a sham protocol for dry needling is required. Recommendations provided in this review may be used to develop sham protocols so that future protocols are more consistent and potentially more effective.

No difference in pressure pain threshold and temporal summation after lumbar spinal manipulation compared to sham: A randomised controlled trial in adults with low back pain

BACKGROUND

Changes in quantitative sensory tests have been observed after spinal manipulative therapy (SMT), particularly in pressure pain thresholds (PPT) and temporal summation (TS). However, a recent systematic review comparing SMT to sham found no significant difference in PPT in patients with musculoskeletal pain. The sham-controlled studies were generally low quality, and conclusions about other quantitative sensory tests could not be made.

OBJECTIVES

We aimed to perform a sham-controlled study with the specific objective of investigating changes in PPT and TS short-term after lumbar SMT compared to sham manipulation in people with low back pain.

METHODS

This was a double-blind randomised controlled trial comparing high-velocity low-amplitude lumbar SMT against sham manipulation in participants with low back pain. Primary outcome measures were PPT at the calf, lumbar spine and shoulder, and TS at the hands and feet. These were measured at baseline, then immediately, 15 min and 30 min post-intervention.

RESULTS

Eighty participants (42 females) were included in the analyses (mean age 37 years), with 40 participants allocated to each intervention group. Significant between-group differences were only observed for calf PPT, which could be explained by a decrease in PPT (increased sensitivity) after SMT and an increase after sham. Feet TS decreased significantly over time after both SMT and sham, and any other changes over time were inconsistent.

CONCLUSIONS

Our results suggest that lumbar SMT does not have a short-term hypoalgesic effect, as measured with PPT and TS, when compared to sham manipulation in people with low back pain.

Effectiveness of chiropractic manipulation versus sham manipulation on recurrent headaches in children aged 7-14 years, Protocol for a randomized clinical trial

Background

Headache is one of the most common pain symptoms in childhood having a negative impact on many aspects of the lives of affected children, both short-term and long-term. Therefore, it is important to document safe and effective treatment options. Chiropractic spinal manipulation is a commonly used treatment option for these patients, although there are no randomized clinical trials documenting the effectiveness of this in pediatric headache. However, there is moderate evidence for effectiveness of spinal manipulation for adults with tension-type and cervicogenic headaches.This paper describes the protocol for a two-armed randomized superiority clinical trial aiming to investigate the effectiveness of chiropractic manipulation versus sham manipulation in the treatment of recurrent headache in children aged 7-14.

Methods

Children with weekly headaches for at least six months will be included if they have indications for chiropractic manipulation. The participants will be randomized to either chiropractic manipulation or sham manipulation. Both children and parents will be blinded for allocation. There will be 100 children in each arm and they will answer weekly text messages four weeks prior to treatment and during a four months treatment period. Potential primary outcomes are weekly number of headaches, intensity of headache, medication use and global perceived effect. Secondary outcomes include side-effects and headache status after one year.An initial outcome data analysis will be performed to inform the choice of primary outcome (adaptive design). Intervention effects will be reported as the difference in mean values between the two treatment arms, Cohen's effect size and numbers needed to treat.

Discussion

A major strength of this study is its pragmatic nature, where the active treatment group receives chiropractic manipulation according to their individual needs, while both groups continue their use of medication for headache according to their pre-trial habits. Other strengths include an elaborate sham procedure and the weekly outcome reports, reducing recall bias.If it is possible to develop effective treatment for headache in children, a life course of recurring problems may be altered with potential positive implications for both individuals and society.

Trial registration

ClinicalTrials.gov, identifier NCT02684916.

Cerebral Perfusion Changes After Osteopathic Manipulative Treatment: A Randomized Manual Placebo-Controlled Trial

Osteopathic Manipulative Treatment (OMT) is a therapeutic approach aimed at enhancing the body's self-regulation focusing on somatic dysfunctions correction. Despite evidence of OMT effectiveness, the underlying neurophysiological mechanisms, as well as blood perfusion effects, are still poorly understood. The study aim was to address OMT effects on cerebral blood flow (CBF) in asymptomatic young volunteers as measured by Magnetic Resonance Arterial Spin Labeling (ASL) method. Thirty blinded participants were randomized to OMT or placebo, and evaluated with an MRI protocol before manual intervention (T0), immediately after (T1), and 3 days later (T2). After T0 MRI, participants received 45 min of OMT, focused on correcting whole body somatic dysfunctions, or placebo manual treatment, consisting of passive touches in a protocolled order. After treatment, participants completed a de-blinding questionnaire about treatment perception. Results show significant differences due to treatment only for the OMT group (OMTg): perfusion decreased (compared to T0) in a cluster comprising the left posterior cingulate cortex (PCC) and the superior parietal lobule, while increased at T2 in the contralateral PCC. Furthermore, more than 60% of participants believed they had undergone OMT. The CBF modifications at T2 suggest that OMT produced immediate but reversible effects on CBF.

The acute effects of joint manipulative techniques on markers of autonomic nervous system activity: a systematic review and meta-analysis of randomized sham-controlled trials

Background

The autonomic nervous system (ANS) interests many chiropractors and manual therapists, because joint manipulative techniques (JMT), e.g. high velocity low amplitude (HVLA) manipulations and mobilizations, appear to produce acute changes in ANS mediated physiology. The complexity of this issue justifies a systematic critical literature review.

Objective

To review the literature comparing the acute changes in markers of ANS activity between JMT applied on spinal or peripheral joints and a sham procedure in healthy or symptomatic subjects.

Method

We searched PsycINFO, PEDro, PubMed, Cochrane library, EMBASE, and Medline up to December 2017. We updated the search with PubMed, Cochrane library, EMBASE, and Medline including July 2018. Inclusion criteria were: randomized sham-controlled trials assessing the effect of JMT on markers of ANS activity; manually applied JMT, regardless of technique, applied on either healthy or symptomatic humans; outcome measurements recorded at baseline and repeated during and/or after interventions. Selection of articles and data extraction were performed independently by two reviewers. The quality of studies was assessed using the Cochrane ‘risk of bias’ tool and a technical check-list. Results were reported narratively with some meta-analyses. The Cochrane GRADE approach was used to assess the certainty of evidence.

Results

Twenty-nine of 2267 studies were included in the synthesis. Mobilizations (oscillatory technique) probably produce an immediate and short-term, bilateral increase in skin sympathetic nerve activity (reflected by an increase in skin conductance) regardless of the area treated (moderate-certainty evidence). It is uncertain whether the sympathetic arousal also explains an increase in respiratory rate (very low-certainty evidence). Our evaluation of the literature suggests that spinal sustained apophyseal glides (SNAGs) mobilization and HVLA manipulation of the spine may have no acute effect on the studied markers of ANS activity (very low- to low-certainty evidence).

Conclusion

Some types of mobilizations probably produce an immediate and short-term, statistically significant increase in skin sympathetic nerve activity when compared to a sham procedure, whereas spinal SNAGs and spinal HVLA techniques may have no acute effect on the studied markers of ANS activity. No region-specific results were noted. The literature suffers from several shortcomings, for which reason we strongly suggest further research.

Electronic supplementary material

The online version of this article (10.1186/s12998-019-0235-1) contains supplementary material, which is available to authorized users.

Innovative treatment of clinically diagnosed meniscal tears: a randomized sham-controlled trial of the Mulligan concept 'squeeze' technique

Objective: The purpose of this study was to assess the effects of the Mulligan Concept (MC) 'squeeze' technique compared to a sham technique in participants with a clinically diagnosed meniscal tear.

Methods: A multi-site randomized sham-controlled trial of participants (n = 23), aged 24.91 ± 12.09 years, with a clinically diagnosed meniscal tear were equally and randomly divided into two groups. Groups received a maximum of six treatments over 14 days. Patient outcomes included the numeric pain rating scale (NRS), patient-specific functional scale (PSFS), the disablement in the physically active (DPA) scale and the knee injury osteoarthritis outcome score. Data were analysed using univariate ANOVA, univariate ANCOVA, and descriptive statistics.

Results: All participants in the MC 'squeeze' group met the discharge criteria of ≤2 points on the NRS, ≥9 points on the PSFS, and ≤34 points or ≤23 on the DPA Scale for chronic or acute injuries, respectively within the treatment intervention timeframe. A significant difference was found in favor of the MC 'squeeze' technique in PSFS scores (F(1, 21) = 4.40, p = .048, partial eta squared = .17, observed power = .52) and in DPA Scale scores (F(1, 21) = 7.46, p = .013, partial eta squared = .27, observed power = .74).

Discussion: The results indicate the MC 'squeeze' technique had positive effects on patient function and health-related quality of life over a period of 14 days and was clinically and statistically superior to the sham treatment. Further investigation of the MC 'squeeze' technique is warranted.

The regional effect of spinal manipulation on the pressure pain threshold in asymptomatic subjects: a systematic literature review

Background

Spinal manipulation (SM) has been shown to have an effect on pain perception. More knowledge is needed on this phenomenon and it would be relevant to study its effect in asymptomatic subjects.

Objectives

To compare regional effect of SM on pressure pain threshold (PPT) vs. sham, inactive control, mobilisation, another SM, and some type of physical therapy. In addition, we reported the results for the three different spinal regions.

Method

A systematic search of literature was done using PubMed, Embase and Cochrane. Search terms were ((spinal manipulation) AND (experimental pain)); ((spinal manipulative therapy OR spinal manipulation) AND ((experimental pain OR quantitative sensory testing OR pressure pain threshold OR pain threshold)) (Final search: June 13th 2017). The inclusion criteria were SM performed anywhere in the spine; the use of PPT, PPT tested in an asymptomatic region and on the same day as the SM. Studies had to be experimental with at least one external or internal control group. Studies on only spinal motion or tenderness, other reviews, case reports, and less than 15 invited participants in each group were excluded. Evidence tables were constructed with information relevant to each research question and by spinal region. Results were reported in relation to statistical significance and were interpreted taking into account their quality.

Results

Only 12 articles of 946 were accepted. The quality of studies was generally good. In 8 sham controlled studies, a psychologically and physiologically “credible” sham was found in only 2 studies. A significant difference was noted between SM vs. Sham, and between SM and an inactive control. No significant difference in PPT was found between SM and another SM, mobilisation or some type of physical therapy. The cervical region more often obtained significant findings as compared to studies in the thoracic or lumbar regions.

Conclusion

SM has an effect regionally on pressure pain threshold in asymptomatic subjects. The clinical significance of this must be quantified. More knowledge is needed in relation to the comparison of different spinal regions and different types of interventions.

Chiropractic management of dominating one-sided pelvic girdle pain in pregnant women; a randomized controlled trial

Background

The aim of this study was to investigate the outcome of chiropractic management for a subgroup of pregnant women with dominating one-sided pelvic girdle pain (PGP).

Methods

The study population was recruited from a prospective longitudinal cohort study of pregnant women. Women reporting pelvic pain (PP), and who were diagnosed with dominating one-sided PGP after a clinical examination, were invited to participate in the intervention study. Recruitment took place either at 18 weeks, or after an SMS-tracking up to week 29. The women were randomized into a treatment group or a control group. The treatment group received chiropractic treatment individualized to each woman with regards to treatment modality and number of treatments. The control group was asked to return to conventional primary health care. The primary outcome measure was new occurrence of full time and/or graded sick leave due to PP and/or low back pain. Secondary outcome measures were self-reported PP, physical disability and general health status. Proportion of women reporting new occurrence of sick leave were compared using Chi squared tests. Differences in secondary outcome measures were estimated using linear regression analyses.

Results

Fifty-Six women were recruited, and 28 of them were randomized into the treatment group, and 28 into the control group. There was no statistically significant difference in sick leave, PP, disability or general health status between the two groups during pregnancy or after delivery.

Conclusion

The study did not demonstrate superiority of chiropractic management over conventional care for dominating one-sided PGP during pregnancy. However, the analyses revealed wide confidence intervals containing both positive and negative clinically relevant effects.

Trial registration

The study was registered in ClinicalTrials.gov (NCT01098136; 22/03/2010).

Spinal Manipulative Therapy and Sports Performance Enhancement: A Systematic Review

OBJECTIVE

The purpose of this study was to review the literature regarding the relationship between spinal manipulative therapy (SMT) and sports performance.

METHODS

PubMed and Embase databases were searched for original studies published up to July 2016. Inclusion criteria were if SMT has been applied to athletes and if any sports performance-related outcome was measured.

RESULTS

Of the 581 potential studies, 7 clinical trials were selected. Most studies had adequate quality (≥6/11) when assessed by the PEDro scale. None of those studies assessed performance at an event or competition. Four studies revealed improvement in a sports performance test after SMT. Meta-analysis could not be performed because of the wide differences in methodologies, design, and outcomes measured. Spinal manipulative therapy influences a wide range of neurophysiological parameters that could be associated with sports performance. Of the 3 studies where SMT did not improve test performance, 2 used SMT not for therapeutic correction of a dysfunctional vertebral joint but to an arbitrary previously set joint.

CONCLUSIONS

Although 4 of 7 studies showed that SMT improved sports performance tests, the evidence is still weak to support its use. Spinal manipulative therapy may be a promising approach for performance enhancement that should be investigated with more consistent methodologic designs.

Chiropractic spinal manipulative therapy for cervicogenic headache: a single-blinded, placebo, randomized controlled trial

Objective

Cervicogenic headache is a disabling headache where pharmacological management have limited effect. Thus, non-pharmacological management is warranted. Our objective was therefore to investigate the efficacy of chiropractic spinal manipulative therapy versus placebo (sham manipulation) and control (continued usual but non-manual management) for cervicogenic headache in a prospective 3-armed single-blinded, placebo, randomized controlled trial of 17 months’ duration.

Results

Nineteen participants were equally randomized into the three groups, and 12 participants completed the randomized controlled trial. Headache frequency improved at all time points in the chiropractic spinal manipulative therapy and the placebo group. Headache index improved in the chiropractic spinal manipulative therapy group at all time points, while it improved at 6 and 12 months’ follow-up in the placebo group. The control group remained unchanged during the whole study period. Adverse events were few, mild and transient. Blinding was concealed throughout the RCT. Thus, our results suggest that manual-therapy might be a safe treatment option for participants with cervicogenic headache, but data need to be confirmed in a randomized controlled trial with sufficient sample size and statistical power.

Trial registration ClinicalTrials.gov identifier: NCT01687881, 11 September 2012

Electronic supplementary material

The online version of this article (doi:10.1186/s13104-017-2651-4) contains supplementary material, which is available to authorized users.

Adverse events in a chiropractic spinal manipulative therapy single-blinded, placebo, randomized controlled trial for migraineurs

BACKGROUND

Unlike pharmacological randomized controlled trials (RCTs), manual-therapy RCTs do not always report adverse events (AEs). The few manual-therapy RCTs that provide information on AEs are frequently without details, such as the type and-, severity of the AE and reason for withdrawal.

OBJECTIVE

To prospectively report all AEs in a chiropractic spinal manipulative therapy (CSMT) RCT.

DESIGN

A prospective 3-armed, single-blinded, placebo, RCT.

METHODS

Seventy migraineurs were randomized to the CSMT or a placebo, with 12 intervention sessions over three months. The recommendations by CONSORT and the International Headache Society's Task Force on AEs in migraine RCTs were followed. A standardized reporting scheme designed for pharmacological RCTs was used, and the AEs were described as frequencies and percentages within each group. The 95% confidence intervals (CIs) for the percentages (absolute risk) of AEs in each group were calculated when possible. Attributable risk (%) and relative risk were calculated with the corresponding 95% CIs.

RESULTS

AEs were assessed in 703 sessions, with 355 in the CSMT group and 348 in the placebo group. Local tenderness was the most common AE, reported by 11.3% and 6.9% of the CSMT group and the placebo group, respectively, and tiredness on the intervention day was reported by 8.5% and 1.4% of CSMT group and the placebo group, respectively. The highest attributable risk was for tiredness on the treatment day, 7.0% (CI 3.9-10.2%) which presented a relative risk of 5.9 (CI 2.3-15.0).

CONCLUSIONS

AEs were mild and transient, and severe or serious AEs were not observed.